<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .container{
            display: grid;
            grid-template-columns: 4fr 400px 3fr;
        }
        .container .left{
            height: 100px;
            background-color: bisque;
        }
        .container .right{
            flex: 3;
            height: 100px;
            background-color: aquamarine;
        }
        .container .center{
            flex: 0 0 400px;
            height: 100px;
            background-color: teal;
        }

        .all{
            display: flex;
            justify-content: center;
            align-items: center;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="left all">
            左
        </div>
        <div class="center all">
            中
        </div>
        <div class="right all">
            右
        </div>
    </div>
</body>
</html>